Nice subject. Seems litle out of focus or unsharp but it doesn´t hurt the image alot. The background and also the foreground seems interesting. Technically pretty well done.
Your picture is really interesting. The composition is very good. I think I would have liked it better if the focus was a bit clearer. The background also detracts from the old piece of machinery - one of those things you can't really change though.
the main subject is not in focus. the grass stem in front of it is though.. the bright branches at the top should be removed (in person cut them, or crop the pic to leave them out)
The grass and twigs make the image a bit cluttered. It's a nice subject, and well photographed too. A different setting, perhaps something with a different color in the background to make the wheel stand out more, might have looked better. Good job.